Firearms can be provided with various features to improve their performance. For example, it is known to employ ports that function to expel combustion gases out of the bore of a barrel of the firearm during discharge. The combustion gases are expelled radially from the bore through the ports so that energy associated with the expelled combustion gases does not contribute to recoil of the firearm. Additionally, porting of combustion gases from the barrel acts to dissipate heat generated during firing and prevents temperature elevation of the firearm after multiple shots are fired.
Additional features that can be incorporated into firearms include knife edges that are arranged longitudinally along the interior of the barrel that act to score a wad as it passes through the bore. The wad may house a plurality of pellets or flechettes. Scoring of the wad by the knife edges may facilitate its rapid opening upon exiting the barrel so that the wad does not interfere with the string of pellets as they travel to their target.
Repeat use of reference characters in the present specification and drawings is intended to represent the same or analogous features or elements of the invention.